Matlab Function for Lagrange Interpolation

My Code is missing two values and I need help:

function y = lagrange (X, Y, x)
n = length(X);
if n ~= length (Y)
    error ('X and Y must have the same length.');
end
y = zeros(size(x));
for i = 1:n
    L = ones(size(x));
    for j = [1:i-1 i+1:n]
        L = %complete missing line
    end
    y = %complete missing line
end
end

[KSSV]

Check this link: https://in.mathworks.com/matlabcentral/answers/3338-lagrange-interpolation-m